title: Role of porosity and pore architecture in the in vivo bone regeneration capacity of biodegradable glass scaffolds.
abstract: The aim of this work is to shed light on the role of porosity and pore architecture in the in vivo bone regeneration capacity of biodegradable glass scaffolds. A calcium phosphate glass in the system P2O5-CaO-Na2O-TiO2 was foamed using two different porogens, namely albumen and hydrogen peroxide (H2O2); the resulting three-dimensional porous structures were characterized and implanted in New Zealand rabbits to study their in vivo behavior. Scaffolds foamed with albumen displayed a monomodal pore size distribution centered around 150 μm and a porosity of 82%, whereas scaffolds foamed with H2O2 showed lower porosity (37%), with larger elongated pores, and multimodal size distribution. After 12 weeks of implantation, histology results revealed a good osteointegration for both types of scaffolds. The quantitative morphometric analysis showed the substitution of the biomaterial by new bone in the case of glasses foamed with albumen. In contrast, bone neoformation and material resorption were significantly lower in the defects filled with the scaffolds foamed with H2O2. The results obtained in this study showed that both calcium phosphate glass scaffolds were osteoconductive, biocompatible, and biodegradable materials. However, differences in porosity, pore architecture, and microstructure led to substantially different in vivo response.
authors.affiliation: Department of Surgery, Faculty of Medicine, Surgical Research Centre, University of Concepcion, 4070386, Concepcion, Chile.
authors.forename: Edgardo S
authors.initials: ES
authors.lastname: Sanzana
authors.forename: Melba
authors.initials: M
authors.lastname: Navarro
authors.forename: Maria-Pau
authors.initials: MP
authors.lastname: Ginebra
authors.forename: Josep A
authors.initials: JA
authors.lastname: Planell
authors.forename: Alvaro C
authors.initials: AC
authors.lastname: Ojeda
authors.forename: Hernan A
authors.initials: HA
authors.lastname: Montecinos
mesh_terms: D000818:Animals; D001861:Bone Regeneration; D018786:Bone Substitutes / Q000737:chemistry*; D002130:Calcium Phosphates / Q000737:chemistry*; D002516:Ceramics / Q000737:chemistry; D005898:Glass / Q000737:chemistry*; D008297:Male; D016062:Porosity; D011817:Rabbits; D054457:Tissue Scaffolds / Q000737:chemistry*
chemical_list: D018786:Bone Substitutes; D002130:Calcium Phosphates; C020243:calcium phosphate
keywords: bone substitutes; calcium phosphate glasses; in vivo; scaffolds; tissue engineering